Poly1305 is a one-time authenticator originally designed by D. J. Bernstein. Poly1305 takes a 32-byte one-time key and a message and produces a 16-byte tag. It can be used to verify the data integrity and the authenticity of a message.

This module provide poly1305 message authentication code (MAC) for V Language. As a note, a key must only be used for a single message. Authenticating two different messages with the same key allows an attacker to forge authenticators for other messages with the same key.